1. Field of the Invention
The present invention relates to an optical disk provided on its back surface opposite the recording/reproducing surface with an image including pictures, characters and/or symbols, a method of forming such an image on an optical disk, an image forming apparatus for carrying out the method of forming an image on an optical disk, and an adhesive layer transfer sheet to be employed in carrying out the method of forming an image on an optical disk.
2. Description of the Related Art
An optical disk, such as a compact disk, a laser disk, a magnetooptic disk or a phase change optical disk, has the front surface serving as a recording surface or a reproducing surface, and the back surface provided with a label in which an image for identifying the optical disk or giving decorative effect to the optical disk is formed. Usually, the image is formed by screen printing or offset printing. When printing an image to form a label on an optical disk by screen printing or offset printing, a printing plate needs to be prepared for each image, increasing printing costs when printing the label on a small lot of optical disks, the printing plate needs to be changed or cleaned to remove the ink every time the image is changed, requiring troublesome processes, reducing productivity and increasing printing costs when printing the label on a small lot of optical disks, screen printing and offset printing are unable to print images in a high resolution and a high sharpness, and it is difficult to form sharp full-color pictures by screen printing or offset printing.
The present invention has been made in view of such problems and it is therefore an object of the present invention to provide an optical disk provided with a clear, highly sharp image including pictures, characters and/or symbols.
Another object of the present invention is to provide a simple method of forming such an image on an optical disk.
A further object of the present invention is to provide an image forming apparatus for carrying out such a simple method of forming such an image on an optical disk.
A still further object of the present invention is to provide an adhesive layer transfer sheet to be employed in carrying out the aforesaid method of forming an image on an optical disk.
According to a first aspect of the present invention, an optical disk provided on one surface thereof with a label is obtained by a method comprising the steps of: forming an image on an intermediate transfer medium by a thermal transfer process; and transferring the image from the intermediate transfer medium onto the surface of the optical disk to form the label on the optical disk.
According to a second aspect of the present invention, an optical disk provided on one surface thereof with an image receptive layer carrying an image and forming a label is obtained by a method comprising the steps of: forming the image on the image receptive layer of an intermediate transfer medium by a thermal transfer process; and transferring the image receptive layer carrying the image from the intermediate transfer medium onto the surface of the optical disk to form the label on the surface of the optical disk.
According to a third aspect of the present invention, a method of forming an image on an optical disk comprises the steps of: forming the image on one surface of an intermediate transfer medium by transferring a coloring matter from a thermal transfer sheet having a color layer by a thermal transfer process; laying the intermediate transfer medium and the optical disk one on top of the other with the image formed on the intermediate transfer medium in close contact with the surface of the optical disk; and transferring the image onto the surface of the optical disk by applying heat and/or pressure to the intermediate transfer medium.
According to a fourth aspect of the present invention, a method of forming an image on an optical disk comprises the steps of: forming the image on an image receptive layer formed on an intermediate transfer medium by transferring a coloring matter from a thermal transfer sheet provided on its surface with a color layer to the image receptive layer of the intermediate transfer medium by a thermal transfer process; laying the intermediate transfer medium and the optical disk one on top of the other with the image receptive layer in close contact with one surface of the optical disk; and transferring the image receptive layer from the intermediate transfer medium to the optical disk by applying heat and/or pressure to the intermediate transfer medium by a transfer means.
According to a fifth aspect of the present invention, an adhesive layer transfer sheet comprises: a base sheet; and an adhesive layer formed on one surface of the base sheet and capable of being peeled off the base sheet.
According to a sixth aspect of the present invention, an adhesive layer transfer sheet comprises: a base sheet; a white layer formed on one surface of the base sheet and capable of being peeled off the base sheet; and an adhesive layer formed on the white layer.
According to a seventh aspect of the present invention, a thermal transfer sheet comprises: a thermal transfer base sheet; a color layer formed on one surface of the thermal transfer base sheet; and an adhesive layer formed on the same surface of the thermal transfer base sheet contiguously with the color layer and capable of being peeled off the thermal transfer base sheet.
According to an eighth aspect of the present invention, an intermediate transfer medium comprises: a transfer base sheet; an image receptive layer formed on one surface of the transfer base sheet and capable of being peeled off the transfer base sheet; and an adhesive layer formed on one surface of the transfer base sheet contiguously with the image receptive layer and capable of being peeled off the transfer base sheet.
According to a ninth aspect of the present invention, a method of forming an image on an optical disk comprises the steps of: preparing a thermal transfer sheet comprising a thermal transfer base sheet and at least a color layer formed on one surface of the thermal transfer base sheet, and an intermediate transfer medium comprising an intermediate transfer base sheet and at least an image receptive layer formed on one surface of the intermediate transfer base sheet; forming the image on the image receptive layer of the intermediate transfer medium by laying the thermal transfer sheet and the intermediate transfer medium one on top of the other with the color layer and the image receptive layer in close contact with each other, compressing the thermal transfer sheet and the intermediate transfer medium between a thermal head and a platen roller, and selectively energizing the heating elements of the thermal head according to image data to transfer a thermomigratory coloring matter contained in the color layer of the thermal transfer sheet from the color layer of the thermal transfer sheet to the image receptive layer of the intermediate transfer medium; and transferring the image receptive layer carrying the image from the intermediate thermal transfer medium to the optical disk by heating the intermediate transfer medium pressed against the optical disk.
According to a tenth aspect of the present invention, an image forming apparatus for forming an image on an optical disk comprises: thermal transfer sheet conveying means for conveying a thermal transfer sheet comprising a thermal transfer base sheet and at least a color layer formed on one surface of the thermal transfer base sheet; intermediate transfer medium conveying means for conveying an intermediate transfer medium comprising an intermediate transfer base sheet and at least an image receptive layer formed on one surface of the intermediate transfer base sheet; image forming means comprising a thermal head and a platen roller, for forming the image on the image receptive layer by laying the thermal transfer sheet and the intermediate transfer medium one on top of the other with the color layer and the image receptive layer in close contact with each other, compressing the combination of the thermal transfer sheet and the intermediate transfer medium between the thermal head and the platen roller, and selectively energizing the heating elements of the thermal head according to image data to transfer a thermomigratory coloring matter contained in the color layer from the color layer to the image receptive layer; and image receptive layer transferring means comprising a heating means, for transferring the image receptive layer carrying the image to the optical disk by laying the intermediate transfer medium having the image receptive layer carrying the image and the optical disk one on top of the other, and heating intermediate transfer medium by the heating means.
According to an eleventh aspect of the present invention, an image forming apparatus for forming an image on an optical disk comprises: intermediate transfer medium conveying means for conveying an intermediate transfer medium comprising an intermediate transfer base sheet and at least an image receptive layer carrying the image formed of a thermomigratory coloring matter contained in the image receptive layer; and image receptive layer transfer means comprising heating means, for transferring the image receptive layer of the intermediate transfer medium to the optical disk by laying the intermediate transfer medium and the optical disk one on top of the other and heating the intermediate transfer medium by the heating means.
According to the present invention, an image is formed on an intermediate transfer medium or on an image receptive layer formed on an intermediate transfer medium and capable of being peeled off the intermediate transfer medium by a thermal transfer process on the basis of image data produced by using a computer or the like. Accordingly, a clear, highly sharp image can be formed on the intermediate transfer medium, and the image or the image receptive layer carrying the image can be transferred intactly to an optical disk to form a label having the image on the optical disk.